The exchanges, which are confined to noncombat training, fall short of the kinds of advanced military exercises that occur between the U.S. and longer-term allies in the region, such as the Philippines and Australia.

But they underscore a push by the U.S. to deepen military ties across Southeast Asia, especially in the face of greater shared concerns over China, which has spent aggressively in recent years to enhance its military capabilities.

The U.S. strategy includes an expansion of training exercises in other parts of the region to include newer participants, such as Cambodia and Malaysia, in some programs, as well as the deployment of new hardware, including littoral combat ships in Singapore.

Although U.S. officials stressed the week of Vietnam exchanges has been planned for months, the maneuvers risk further straining relations with China at a time when tensions already are high because of disputes over the South China Sea, a potentially oil-rich area where Vietnam, the Philippines, Taiwan, Brunei, Malaysia and China all have conflicting territorial claims. The Philippines, which has complained about Chinese intimidation of oil-exploration vessels recently, last week told China it plans to raise disputes over the South China Sea with a United Nations tribunal—a proposal China promptly rejected.

Vietnam, which accused China of interfering with one of its oil-exploration boats in June, has allowed anti-China protests in recent weeks, including a march on Sunday, the Associated Press reported. Demonstrations are rare in Vietnam, and are typically quashed quickly by police. Sunday's march by a few protesters shouting "Down with China," and carrying signs in carrying signs in English, Chinese and Vietnamese—one reading, "China stop invading Vietnam. Stop murdering Vietnamese fishermen"—was limited, according to the AP. The police first rounded up a couple of dozen protesters and took them off in buses, then herded those who remained away from an area near the Chinese Embassy. Some of the marchers were later detained.

Gen. Chen Bingde, chief of the General Staff of the Chinese People's Liberation Army, said Monday the timing of U.S. naval exercises with Vietnam and also recently with the Philippines was "inappropriate" in light of the South China Sea issues.

On Friday, Adm. Mike Mullen, chairman of the U.S. Joint Chiefs of Staff, said at a news conference in Tokyo that recent meetings with Chinese military leaders including Gen. Chen were "productive and generally positive," though he noted "there is a long way to go."

The push to expand cooperation between the U.S. and some Southeast Asian nations presents its own challenges, especially between the U.S. and Vietnam, which normalized relations in 1995, 20 years after the Vietnam War. Both countries are wary of going too far and possibly antagonizing China.

Meanwhile, some top Vietnamese leaders remain suspicious of U.S. motives. They worry the U.S. intends to more aggressively promote democratic changes in Vietnam or to support human-rights activists whose work could undermine the government there, according to people familiar with discussions between the two countries.

Warming Ties

Military and political links have grown between U.S., Vietnam

1975: War in Vietnam ends

1994: U.S. lifts trade embargo against Vietnam

2000: First visit by a U.S. Defense Secretary since war

2008: First strategic dialogue on security and other issues

2010: Joint naval exchanges held

Still, relations have for the most part blossomed in recent years, with rapidly expanding trade and investment ties. Military cooperation has gradually expanded since the first U.S. warship visited the country since the Vietnam War in 2003 and last year included some training exercises.

U.S. officials also are looking to boost training programs elsewhere in Southeast Asia as part of a wider strategy to enhance its ability to police international waterways, and to lift the confidence and military capabilities of smaller Southeast Asian countries, some of which have privately questioned the U.S.'s commitment to the region as it devotes resources to the Middle East.

At the annual Shangri-La Dialogue Asian security meeting in Singapore last month, U.S. Defense Secretary Robert Gates said the U.S. military would be "increasing its port calls, naval engagements, and multilateral training efforts" in the region to "help build partner capacity to address regional challenges." Those efforts, he said, included stepped-up cooperation with Singapore with the deployment there of littoral combat ships, which are relatively new and fast combat vessels designed to operate close to shorelines.

Other efforts include the expansion this year of annual Cobra Gold exercises between the U.S., Thailand and other Asian countries to include Malaysian troops for the first time. The Cooperation Afloat Readiness and Training, or Carat, program that involves bilateral military exercises between the U.S. Navy and more than a half-dozen Asian countries, recently expanded to include Cambodia and is adding Bangladesh. In June, Carat exercises with Malaysia included a U.S. attack submarine for the first time in the exercise's 17-year history.

"The exercises are becoming more complex and of longer duration," and tend to involve a larger number of countries than in the past, said
Ian Storey,
a fellow at the Institute of Southeast Asian Studies in Singapore.

Weekend Investor

"I think this is going to make the Chinese quite nervous" as the U.S. tries to expand its presence there, added
Bonnie Glaser,
a senior fellow at the Center for Strategic and International Studies in Washington.

This year's Vietnam activities, held in the port city of Danang, include two guided missile destroyers, the USS Chung-Hoon and USS Preble, as well as a rescue and salvage ship, while last year's activities involved the USS John S. McCain warship. The activities also will feature an increased number of noncombat activities, such as search-and-rescue missions and navigation training, as well as some cultural and trust-building exercises, including community-service projects.

"We've had a presence in the Western Pacific and the South China Sea for 50 to 60 years, even going back before World War II,"' Rear Adm.
Tom Carney,
who is leading the naval exchange, told reporters in Danang, according to the Associated Press. "We have no intention of departing from that kind of activity."

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